There are many, many types of apparatus designed to lock a door in position, whether it be closed, partially open, or at any position. Several of the prior art citations listed below incorporate a small locking pin in addition to the main hinge pin (or pintle). These U.S. citations are: U.S. Pat. Nos. 6,591,453; and 7,891,056; 3,969,788. U.S. Pat. No. 4,844,519 uses a pin to lock a hinge-looking apparatus that is installed on the latch side of the door, not the hinge side; furthermore, it only locks a door in the closed position.
Certain door locks or stays work in completely different manners than the present invention. U.S. Pat. No. 3,325,854 holds a door open by placing a triangular piece of material in the hinge crack; it is not adjustable. U.S. Pat. No. 2,550,626 operates by means of a piston and cylinder imbedded in the door jamb and wall. U.S. Pat. No. 3,341,240 operates by pivoting a door-stop-mounted adjustable rod into the hinge crack to prevent closure—this does not prevent the door from opening further. U.S. Pat. No. 4,630,333 operates by compressing the hinge knuckle around a hinge pin made of thermoplastic. U.S. Pat. No. 773,717 describes a hinge that holds a door open by providing friction between a spring-loaded pin and a disc in the hinge. With the friction system, the door is not “locked” into position, it is merely harder to move and resistant to only light drafts and pushing. Similarly, U.S. Pat. No. 7,096,536 uses friction between two detent discs to provide “dwell points” in the arc of a car door; the car door is never locked at any one position, it simple has preferential resting points. U.S. Pat. No. 6,497,005 discloses a hinge-mounted doorstop that is adjustable, but it only functions to stop a door from opening past a certain point—it does not lock the door into any given position.
Some prior art citations listed below do not address the functionality of the present invention at all, or address different types of “doors.” U.S. Pat. No. 820,995 discloses a multiple stay hinge which does not provide any of the door stop/locking/stay functionality of the present invention. U.S. Pat. No. 7,322,629 discloses a way of locking the hinge in a multiple panel apparatus covering a storage cavity in the floor of an automobile. U.S. Pat. Nos. 5,408,726 and 5,774,938 provide a locking ratchet device for a door that holds a door open in the furthest open position reached. The apparatus in these two patents is a safety device for holding open the emergency door of a bus, and does not “lock” a door in position—the door is free to open further at anytime, the ratchet simply prevents the door from slamming shut once opened. It is not designed for residential door use.
There are a number of prior art citations that are similar to the present invention in functionality. These citations all modify the central hinge pin to provide the locking functionality. This is accomplished in two ways: compressing “teeth” together, or fitting contoured male and female parts together. Bushko, Beeril, and Baker all use a mechanism to force the end of the hingepin against a toothed surface to provide the locking action. Griego and the two Van Gennep applications use a sliding pin where polygonal or star shaped male plugs slide into female sockets to provide the locking action.
These latter inventions are similar to the present invention in functionality. However, there are key differences that distinguish the present invention from these prior art citations. First, we note that the closest prior art incorporates the locking mechanism into a load-bearing hinge. That immediately distinguishes the present invention, since it is not load-bearing. Second, the present invention is not a hinge at all—all of the prior art use the hinge pin in some fashion to effect the locking. The present invention does not have a hinge pin. There is no bearing surface within the present invention that can provide hinge functionality. The present invention works in conjunction with the existing hinges—it does not replace them. Third, the present invention is not installed like a hinge—it is not mortised into the jamb. The present invention utilizes the space between the door and the jamb by keeping the wings especially thin. The wings are in a different configuration than butt hinges in that they are offset. Fourth, the present invention does not modify the action of any existing hinge or attach to a hinge, it provides the functionality independently of the hinges.
Below follows a summary of the known relevant prior art.
U.S. Pat. No. 773,717 (1904) to Craver et al. discloses a door hinge having one leaf formed with a circular plate extending through the knuckles. A spring-loaded pin in the enlarged knuckle beneath the plate pressed against the plate, creating enough friction in the hinge such that the door will tend to stick in whatever positions it is placed, even with small drafts.
U.S. Pat. No. 820,995 (1906) to Smith discloses a door hinge with four leaves, all wrapped around a single pintle. The leaves are then attached such that a leaf attaches to both sides of the door, and a leaf attaches to both sides of the door frame.
U.S. Pat. No. 2,427,384 (1947) to Bushko discloses a door hinge containing two pin members in the knuckles. The lower pin is fixed, and has teeth on its top surface, the upper pin can slide in the knuckles, and its lower surface also has teeth. There is a spring pushing the top pin downward such that the teeth engage and lock the two pin members together, thus prevention the door from opening or closing. The spring can be held back with a cam arrangement so that the door may be position. Thus, a door can be locked in place in a variety of position, including fully closed.
U.S. Pat. No. 2,550,626 (1951) to Vollmer discloses a door stop that slows a door closing or locks it in an open position—it comprises a sleeve and sliding piston embedded in the door casing. This piston is connected to the door by an arcuate head portion screwed into the edge of the door. Friction between the piston and the sleeve slows the closing of the door. The piston is such that rotating the piston rod expands or constricts the friction surface of the piston, increasing/decreasing/stopping the closing speed of the door.
U.S. Pat. No. 3,325,854 (1967) to Steigerwald discloses a door stop consisting of an angled piece of resilient material attached to the top of the pintle by a swiveling link. Thus, the material can be positioned such that it forms wedge between the door and the door jamb, holding it open. It also can be flipped through the door crack and used on the outside, preventing the door from opening beyond a certain point. There is no adjustability as to the angle the door is held open.
U.S. Pat. No. 3,341,240 (1967) to Hazard discloses a door stop consisting of a pivoting blocker attached to the door stop on the door jamb. When pivoted out of the way, the door closes normally. When the door opens, the door stop can be pivoted into the space between the door and the jamb. A longitudinally adjustable member adjusts how far open the door is held.
U.S. Pat. No. 3,629,900 (1971) to Beeril discloses locking door hinges as regular butt hinges where the pintle has toothed caps on each end. The teeth from these caps mesh with teeth on the top and bottom knuckle. The pintle extends beyond the top knuckle, where a cam lever makes it possible to tighten the pintle such that the teeth are tightly engaged against the knuckles, thereby locking the door in any position open or closed.
U.S. Pat. No. 3,744,085 (1973) to Griego discloses a door hinge where the pintle has polygonal plugs spaced along its length. The leafs of the hings have matching polygonal sockets where the knuckles are. The pintle is held by a spring on the end such that the polygonal plugs engage the sockets and hold the door in a set position. To operate the door, the user presses down on the pintle, which slides such that the polygonal plugs are no longer in the sockets, and the hinge leafs are free to rotate about the pintle in normal fashion. When the desired door position is reached, releasing the spring raises the pintle so that the polygonal plugs again engage the sockets and the door will not move.
U.S. Pat. No. 3,969,788 (1976) to McCullough discloses a hinged door lock that can be used in place of the strike plate or as hinge itself for cabinet doors. If one leaf replaces the strike plate, the other leaf extends out and folds over the closed door. A locking pin then holds the lock hinge in a 90-degree angle, locking the door itself. If used as a hinge, the door is attached to the second leaf, and when closed the locking pin inserts into the pintle, locking the door in place (hinge leaves in a 90 degree angle).
U.S. Pat. No. 4,630,333 (1986) to Vickers discloses an adjustable friction hinge made of thermoplastic material. One leaf has two knuckles, and holds the hinge pin. The other leaf has a single knuckle with an adjusting screw, such that the adjusting screw tightens the knuckle, clamping the hinge pin. By adjusting the tightness of the adjusting screw, friction around the hinge pin is set such that the hinge still rotates under force, but remains in position when no active force is applied.
U.S. Pat. No. 4,844,519 (1989) to Dagon discloses a door lock with locking pin. This lock has one plate attached to the door jamb and the other plate attached to the door itself, such that when the door is closed, knuckles extending from the plates mesh together and form a channel through which a pin is placed. This device only locks a door in closed position, not in any position determined by the user.
U.S. Pat. No. 5,173,993 (1992) to Baker discloses a locking door hinge where the pintle is keyed to remain fixed with respect to one hinge plate. On top of the pintle is a locking clutch mechanism consisting of pressure and spocket plates which are adjustable to allow retention of the door in any pivotal position.
U.S. Pat. No. 5,408,726 (1995) to Kent discloses a ratchet locking device that when retrofitted to an existing door hinge, automatically locks the door in an open position. This is envisioned for a school bus emergency exit door, such that, no matter the position of the door, as it is opened, the ratchet locks it open at the farthest point of travel, thus allowing escape without the door swinging shut. There is a release mechanism to allow the door to shut when necessary.
U.S. Pat. No. 5,774,938 (1998) to Kent discloses the same idea as U.S. Pat. No. 5,408,726, with improvements to the apparatus disclosed there.
U.S. Pat. No. 6,497,005 (2002) to Apostoloff discloses a door stop that only prevents a door from opening beyond a pre-determined setpoint. This is a metal door stop that attaches to the existing hingepin and is adjustable to limit the opening of the door.
U.S. Pat. No. 6,591,453 (2003) to Jenks discloses a locking hinge system where the knuckles extend out beyond the hinge pin aperture and have a second aperture that receives a locking pin. The knuckle extensions align together when the door is closed, allowing the pin to be inserted into the second aperture, preventing the door from being opened. When the door swings open past 90 degrees, the extensions pass by each other, such that if the pin is now inserted into the second aperture, it prevents the door from swinging shut. The two locked positions are either fully closed or greater than 90 degrees open, there is no adjustment.
U.S. Pat. No. 7,096,536 (2006) to Johnson discloses a hinge apparatus with cam plates attached to each hinge part. The hinge pin connects the parts centrally though the cam plates. The cam plates have detents in them, and ride on each other. As the door opens, the cam plates rotate and tend to resist rotation when the detents match up. Envisioned for a car door, the hinges tend to hold the car door open at certain points.
U.S. Pat. No. 7,891,056 (2011) to McAfee discloses a locking door hinge that holds a door in predefined positions by means of a pin in the barrels of the hinge connecting them together. The hinge barrels will have small holes down through them at different positions corresponding to different angles of openness. At each available locking position, certain holes will line up, allowing the locking pin to connect the barrels of the hinge and hold the door in position.
U.S. Pat. Application Publication No. 2010/0218344 to Van Gennep discloses a door hinge assembly consisting of a hinge pin and a cylindrical channel having surfaces at one end of the pin and channel designed to mesh together in a locked fashion (star, polygonal, etc). The hinge pin is able to slide up and down through the cylindrical passage through the hinge knuckles such that when the hinge pin is elevated, the meshing surfaces do not meet, and the hinge is free to pivot as any normal hinge would. When the hinge pin is pressed down, the contoured surface on the end of the pin slides down into the meshing surface of the lower knuckle. The hinge pin is held fast to the other hinge leaf by the means of detents. Thus, when the pin is down, the hinge is locked in position. A helical spring is optionally specified to hold the hinge pin up (the unlocked position).
U.S. Pat. Application Publication No. 2011/0094058 to Van Gennep consists of a continuation-in-part of U.S. Pat. App. Pub. No. 2010/0218344.
In summary the present invention provides a non obvious improvement over the prior art door jamb locks. The present invention is installed to an existing hinge mounted door between the door and the jamb itself. Opposing wings can be locked by engaging a gear assembly merely by pushing down on the wing pivot pin that connects the opposing wings.